Knife



G. G. LARSON July 8, 1969 KNIFE Sheet Filed April 17. 1967 Ill r0. 2.

1 I [W] 13 m f/vvewroe. 050265 0. L02 sou B V v flrroxalvss V G. G.LARSON July 8, 1969 KNIFE Sheet 2 Filed April 17, 1967 ya a 3 Q Q J mm MZ M v 0 3 M wN United States Patent U.S. Cl. 30-162 13 Claims ABSTRACTOF THE DISCLOSURE A utility knife to be carried on a key chain, or thelike, the knife having a handle defining a central. guideway which openslongitudinally through the ends of the handle and laterally through aslot in one side of the handle, and a removable blade-actuating slidemovable in the guideway including a resilient beam supported at its endson the handle andprojecting through the handle slot for lateraldeflection of the beam by finger pressure to retract a central lockingdetent on the beam from locking notches in the handle, whereby a bladeattached to the slide may be selectively extended from and retractedinto the handle by longitudinal movement of the slide relative to thehandle, the blade may be selectively locked in various extended andretracted positions by engagement of the slide detent in the handlelocking notches, and the llilade may be replaced by removal of the slidefrom the andle.

This invention relates generally to cutlery devices. More particularly,the invention relates to a small utility knife characterized by areplaceable blade, which may be selectively extended from and retractedinto the knife handle and releasably locked in various extended andretracted positions relative to the handle.

Small utility knives of the kind to which this invention pertains havemany and varied uses in everyday life. Among those who may employ thepresent knife to great advantage, for example, are office workers,shipping clerks, sportsmen, and hobbyists. Small utility knives areparticularly desirable for the reason that they may be convenientlycarried by the user and are thus available for immediate use at anytime.

It is a general object of this invention to provide an improved utilityknife of the character described.

A more specific object of the invention is to provide a utility knifecharacterized by a handle mounting a bladeactuating slide with aresilient beam against which finger pressure may be exerted to initiallydeflect thebeam section out of locking engagement with the handle, andthereafter move the slide relative to the handle to extend and retractthe knife blade.

Another object of the invention is to provide a utility knife of thecharacter described, wherein the blade slide is easily inserted in andremoved from the handle to replace the knife blade.

A further object of the invention is to provide a utility knife of theCharacter described, the handle and blade slide of which are adapted forfabrication from synthetic resin by an injection molding process.

This invention possesses many other advantages, and has other objectswhich may be made more clearly apparent from a consideration of a formin which it may be embodied. This form is shown in the drawingsaccompanying and forming part of the present specification. It will nowbe described in detail, for the purpose of illustrating the generalprinciples of the invention; but it is to be understood that suchdetailed description is not to be taken in a limiting sense, since thescope of the invention is best defined by the appended claims.

Referring to the drawings:

FIGURE 1 is a top plan view of a utility knife according to theinvention, illustrating the knife blade partially extended;

FIG. 2 is an edge view of the knife illustrated in FIG. 1;

FIG. 3 is an enlarged longitudinal section through the knife taken alongthe line 33 in FIG. 1;

FIG. 4 is a transverse section taken along the line 4-4 in FIG. 3;

FIG. 5 is a transverse section taken along the line 5-5 in FIG. 3;

FIG. 6 is a fragmentary longitudinal section through the knife takenalong the line 66 in FIG. 5;

FIG. 7 is a fragmentary longitudinal section through the knife, similarto FIG. 3, illustrating the manner in which the blade slide is removedfrom the knife handle to replace the knife blade; and

FIG. 8 is an enlarged exploded perspective view of the blade slide andblade of the present utility knife.

In general terms, the invention provides a utility knife, represented inthe drawings by the knife 10, including a handle 12 having a centralguideway 14 opening longitudinally through the ends of the handle andlaterally through a slot 16 in one side of the handle extendinglengthwise of the guideway 14. The handle 12 includes a flange 18 whichbounds the slot 16 along one longitudinal side thereof and projectslaterally over the guideway 14. Disposed within and movable lengthwiseof the guideway 14 is a blade-actuating slide 20 having; a rear fingerengaging portion 22 and a forward blade connecting portion 24. The rearfinger engaging portion 22 of the slide 20 includes a longitudinallyextending, laterally resilient beam 26 which projects through the handleslot 16 for engagement by a finger of the users hand. Joined to the endsof the beam 26 are supports 28, .30 which slidably engage the handle 12.A locking detent 32 projects laterally from the beam 26 at a positionapproximately midway between the beam supports 28, 30 for selectiveengagement in a number (shown as 3) of locking notches 34, 36, 38 in theknife handle 12. Engagement of the slide detent 32 in any one of thenotches 34, 36, 38 locks the blade slide 20 in a corresponding fixedposition relative to the knife handle 12. The slide is movable toanother position relative to the handle by exerting inward fingerpressure on the beam 26 of the slide to initially deflect this sectionlaterally inwardly of the handle and thereby retract the slide detent 32inwardly from its current receiving locking notch 34, 36 or 38, as thecase may be, into the guideway 14. The slide is then movedlongitudinally of the handle by extering longitudinal finger pressureupon the depressed slide beam. A blade 40 attached to the forward bladeconnecting portion 24 of the slide may thus be extended from andretracted into the forward end of the handle 12 by moving the slide 20back and forth relative to the handle. The blade may be releasablylocked in various extended and retracted positions by engagement of theslide detent 32 in the handle locking notches 34, 36, 38.

The slide 20 is removable through the rear end of the handle 12 toreplace the blade 40. Normally, however, rearward movement of the slidefrom the handle is prevented by engagement of the rear portion 22 of theslide with a limit stop 42 on the handle flange 18. According to afeature of the invention, removal of the slide 20 from the handle 12 isaccomplished by laterally deflecting the rear portion 22 of the slideoutwardly through the slot 16, laterally of and away from the handle, inthe manner shown in FIG. 7, to retract the rear slide portion clear ofthe limit stop 42, and then sliding the forward blade connecting portion24 of the slide, and the blade attached thereto, rearwardly through therear open end of the handle guideway 14. Preferably, outward lateraldeflection of the rear slide portion 22 away from the handle 12 canoccur only when the slide occupies a forward or extended position withrespect to the handle. The possibility of inadvertent separation of theslide 20 and blade 40 from the handle 12, when the knife is pocketed, isthereby prevented. To this end, the slide detent 32 has a forwardlyextending shoulder 44 engageable under handle flange 18 when the detentis positioned in either of the two rear handle locking notches 36, 38 toprevent the slide from deflecting laterally of the handle, in the mannerillustrated in FIG. 7. The remaining forward locking notch 34 is widerthan the two rear locking notches 36, 38, and has a width, measuredlengthwise of the handle 12, slightly greater than the overall width ofthe slide detent 32 and its shoulder 44. Accordingly, when the bladeslide 20 is in its forward position relative to the handle 12, whereinthe detent 32 engages in the forward handle locking notch 34, the rearportion 22 of the slide may be sprung laterally away from, or outwardlyof, the handle to effect separation of the slide and handle, in themanner just explained.

Referring now in more detail to the utility knife 10 illustrated in thedrawings, the knife handle 12 comprises a plastic body which may beinjection molded to any desired shape, such as the illustrated keyshape. This key shape of the knife handle has no particular functionalutility and was selected merely because of its novelty appeal. In thisconnection, the knife may be conveniently eqiupped with a key chain 46for holding a group of keys.

As shown best in FIG. 4, the handle guideway 14 is generally rectangularin transverse cross-section and has a width, measured laterally of thehandle 12, which is somewhat greater than the width of the handle slot16. The guideway and slot thus together define the handle flange 18,which bounds the slot along one longitudinal side thereof, and anopposing, somewhat narrower flange 48 bounds the slot along its oppositelongitudinal side. The locking notches 34, 36, 38 are spaced along andopen through the inner longitudinal edge of the wide flange 18. In theparticular knife illustrated, the flanges 18, 48 terminate a distanceforwardly of the rear end of the handle 12, and the slide limit stop 42projects inwardly from the longitudinal edge of the flange 18 at theextreme rear end of this flange. Extending through the handle 12,rearwardly of the flanges 18, 48, is an opening 50 for receiving a ringon the key chain 46. The slot 16 terminates a distance rerawardly of thefront end of the handle 12. Forwardly of the slot, the handle guideway14 is closed on all sides. The front end of the guideway defines anarrow slit for receiving the blade 40.

The blade-actuating slide, like the knife handle 12, may be fabricatedfrom a suitable plastic by an injection molding process. As may be bestobserved in FIG. 8, the rear beam 26 of the slide has a generally flatrectangular shape and is made sufficiently thin in transverse section tobe resiliently flexible. The front and rear beam supports 28, 30 extendgenerally normal to the beam and are integrally joined intermediatetheir ends to the ends of the beam, whereby the rear slide portion 22has a generally H configuration in side elevation, as shown. Theprojecting upper ends of the beam supports have substantially the samewidth as the beam and extend substantially equal distances above thebeam to define raised shoulders 52 at the ends of the beam. Theprojecting lower ends of the beam supports define front and rearsupporting legs 54, 56, respectively, on the beam, the rear beam leg 56being somewhat longer than the front beam leg 54. In addition to theupper shoulder 52 and lower beam support leg 56, the' rear beam support30 includes a rear bevelled apron 58. The slide detent 32 comprises anintegral, block-like formation which projects laterally from onelongitudinal side edge of the beam 26 midway between the beam supportlegs 54, 56.

As noted earlier, and hereinafter explained in more detail, theblade-actuating slide 20 is adapted to be initially released formovement relative to the knife handle 12 by inward finger pressure onthe slide beam 26 to deflect the latter toward the handle and thereaftermoved longitudinally of the handle by longitudinal finger pressure onthe beam. To aid initial release of the slide, the upper surface of thebeam is formed with a raised button 60 midway between the ends of thebeam against which finger pressure may be exerted to deflect the beam toits released position. Subsequent longitudinal movement of the slide isaided by the beam end shoulders 52, by serrations 62 which are formed inthe upper surface of the beam, and by a fingernail slot 63 in the button60.

The forward blade connecting portion 24 of the bladeactuating slide 20comprises a relatively thin, flat tongue having a tapered forward end.This tongue 24 is integrally joined at its rear end to and extendsforwardly from the lower end of the front beam support leg 54. The widthof the tongue exceeds the width of the beam 26 and its support legs 54,56. Integrally formed on the undersurface of the tongue are a pair ofdepending circular lugs or pins 64, which are dimensioned to fit snuglybut removably in a pair of mating circular openings 66 in the knifeblade 40, thus to releasably secure the blade to the tongue.

As shown best in FIGS. 4 and 5, the width of the slide beam 26 and itsbeam supports 28, 30 approximates the width of the handle slot 16. Thewidth of the slide tongue 24 approximates the width of the handleguideway 14, just below the handle flanges 18, 48. The knife blade 40,on the other hand, has a width which exceeds the width of the guideway.The opposite vertical walls of the guideway have longitudinal grooves 68to receive the longitudinal side edges of the blade. These grooves arecoextensive with and extend through the front and rear ends of theguideway, as shown.

When the utility knife 10 is assembled, the bladeactuating slide 20 isdisposed within the rear end of the handle guideway 14, in such a waythat the rear beam 26 and the upper shoulder ends 52 of the beamsupports 28, 30 project laterally through the handle slot 16. The lowerend of the rear beam support leg 56 rests slidably on the bottom wall ofthe guideway 14. The tongue 24 of the slide extends forwardly into theforward closed portion of the guideway, just below and in slidingcontact with the undersurfaces of the handle flanges 18, 48. The knifeblade 40 is secured by the pins 64 to the undersurface of the slidetongue 24 and extends forwardly from the tongue with the side edges ofthe blade engaging in the guideway grooves 68. The clearance between theblade 40, when thus disposed in the grooves 68, and the handle flanges18, 48 is just slightly greater than the thickness of the tongue 24,whereby the tongue pins 64 are restrained against movement from theblade openings 66.

Assuming the blade-actuating slide 20 to be in a position wherein itsdetent 32 is aligned with one of the locking notches 34, 36 or 38 in thehandle flange 18, the inherent resiliency of the slide beam 26 urges thelatter to its normal unstressed position illustrated in solid lines inFIGS. 3 and 6, wherein the detent engages in an aligned notch to lockthe slide and the blade 40 attached thereto against longitudinalmovement relative to the knife handle 12. Movement of the slide andblade relative to the handle is accomplished by first exerting inwardfinger pressure on the slide beam 26, in the direction of the arrow inFIG. 3, to deflect the beam inwardly or toward the handle to its brokenline position in the latter figure, which retracts the slide detent 32inwardly from its aligned locking notch into the handle guideway 14,releasing the slide and blade for movement relative to the handle.Thereafter, the finger pressing on the beam is urged forwardly orrearwardly to move the slide and blade forwardly or rearwardly, as thecase may be. The parts of the knife are dimensioned to permit movementof the slide 20 and blade 40 between a fully retracted position, whereinthe blade is completely enclosed within the knife handle 12, and a fullyextended position (FIG. 7), wherein the blade extends a distanceforwardly of the handle. The locking notches 34, 36, 38 in the handleare so located that engagement of the slide detent 32 in notch 34 blocksthe blade in its fully extended position, engagement of the detent innotch 38 locks the blade in its fully retracted position, and engagementof the detent in notch 36 locks the blade in an intermediate, partiallyextended position (FIGS. 1, 2 and 3). Adjustment of the blade to itsintermediate position conditions the knife for slicing relatively thickmaterials, such as cardboard cartons. Adjustment of the blade to itsfully extended position conditions the knife for slicing paper and otherrelatively thin sheet materials.

Forward extension of the blade 40 relative to the knife handle 12 islimited by engagement of the front beam support 28 of the slide 20 withthe front end wall of the handle slot 16. Rearward retraction of theblade relative to the handle is limited by engagement of the rear beamsupport 30 of the slide with the handle limit stop 42.

Removal of the slide 20 and blade 40 from the knife handle 12, toreplace the blade, is accomplished by first moving the slide and bladeto their fully extended position, wherein the slide detent 32 is alignedwith the forward locking notch 34 in the handle, which, as notedearlier, has a width, measured lengthwise of the handle, slightlygreater than the corresponding overall width of the detent 32 and itsshoulder 44. The rear portion 22 of the slide is then bent or deflectedlaterally outward through the handle slot 16, as illustrated in FIG. 7,to retract the detent outwardly from the notch 34 and clear of thehandle flange 18. Thereafter, the slide 20 is moved rearwardly relativeto the handle to withdraw the slide tongue 24 and blade 40 attachedthereto from the handle, through the rear open end of the handleguideway 14. The blade may now be removed from the tongue pins 64 andreplaced by a new blade. Reassembly of the slide 20 and blade 40 in theknife handle 12 is elfected by reversing the above procedure.

One feature of the invention resides in the fact that when the slidedetent 32 is engaged in either of the two relatively narrow, rear handlelocking notches 36 or 38, the detent shoulder 44 engages under thehandle flange 18, in the manner illustrated in FIG. 6, to prevent therear slide portion 22 from deflecting outwardly relative to the knifehandle 12. The detent shoulder 44 is thus effective to preventinadvertent separation of the slide 20 and blade 40 from the knifehandle '12, when the knife is pocketed with the blade retracted. Asnoted earlier, the key shape of the knife handle 12 has no particularutility, but is desirable from the novelty standpoint, particularly whenthe knife is attached to a key chain 46.

I claim:

1. In a knife: a handle having a central guideway opening longitudinallythrough the forward end of said handle and laterally through alongitudinal slot in one side of said handle, a blade-actuating slidewithin and movable lengthwise of said guideway, said slide having frontand rear portions, said rear slide portion including a longitudnallyextendng laterally resilient beam projecting through said slot forengagement by a finger of the users hand, means slidably supporting saidbeam on said handle at two longitudinally spaced supporting locations,whereby said beam is adapted to be deflected inwardly toward said handleby finger pressure on said beam intermediate said supporting locations,and coacting releasable locking means on said beam and handle fornormally locking said slide against movement relative to said handle andadapted to be released by inward deflection of said beam toward saidhandle to permit movement of said slide relative to said handle, saidfront slide portion including blade connecting means for attaching tosaid slide a knife blade to be extended and retracted relative to saidhandle by longitudinal movement of said slide relative to said handle,said guideway opening through the rear end of said handle, said handlehaving a limit stop spaced longitudinally from the locking means on saidhandle and engageable with said slide rear portion to prevent movementof said slide through the rear end of said guideway, said rear slideportion having a width no greater than the Width of said slot and beingdeflectable laterally of and away from said handle through said handleslot to permit said rear slide portion to clear said limit stop andthereby condition said slide to move rearwardly through the rear end ofsaid guideway.

2. A knife according to claim 1; wherein said coacting locking meanscomprise a flange on said handle bounding said slot along onelongitudinal side thereof and extending over said guideway, a lockingnotch in the edge of said flange, and a detent on said beam engageablein said notch to lock said slide against movement relative to saidhandle and adapted to be retracted from said notch into said guideway byinward deflection of said beam toward said handle to release said slidefor movement relative to said handle.

3. A knife according to claim 2; wherein said flange has a. secondlocking notch for receiving said detent, said notches being spacedlengthwise of said handle, whereby said slide may be selectively lockedin two different positions relative to said handle.

4. In a knife: a handle having a central guideway opening longitudinallythrough the forward end of said handle and laterally through alongitudinal slot in one side of said handle, a blade-actuating slidewithin and movable lengthwise of said guideway, said slide having frontand rear portions, said rear slide portion including a longtudinallyextending laterally resilient beam projecting through said slot forengagement by a finger of the users hand, means slidably supporting atleast one end of said beam on said handle, whereby said beam is adaptedto be deflected inwardly toward said handle by finger pressure on saidbeam, and coacting releasable locking means on said beam and handle fornormally locking said slide against movement relative to said handle andadapted to be released by inward deflection of said beam toward saidhandle to permit movement of said slide relative to said handle, saidfront slide portion including blade connecting means for attaching tosaid slide a knife blade to be extended and retracted relative to saidhandle by longitudinal movement of said slide relative to said handle;said coacting locking means comprising a flange on said handle boundingsaid slot along one longitudinal side thereof and extending over saidguideway, longitudinally spaced locking notches in the edge of saidflange, and a detent on said beam engageable selectively in said notchesto lock said slide against movement relative to said handle and adaptedto be retracted from said notches into said guideway by inwarddeflection of said beam toward said handle to release said slide formovement relative to said handle; wherein said guideway opens throughthe rear end of said handle, said handle has a limit stop spacedlongitudinally from the rearmost of said locking notches and engageablewith said rear slide portion to prevent movement of said slide throughthe rear end of said guideway, said rear slide portion having a width nogreater than the Width of said slot and being deflectable laterally ofand away from said handle through said handle slot when said detent isaligned with one looking notch to locate said rear slide portion in aposition wherein said latter portion clears said limit stop and therebyconditions said slide for separation from said handle by rearwardmovement of said slide through the rear end of said guideway.

5. A knife according to claim 4; wherein said detent has a shoulderwhich extends under said flange to restrain said rear slide portionagainst outward deflection relative to said handle when said detentengages in the other locking notch, said one notch is wider than saidother notch and has a width slightly greater than the overall 7 width ofsaid detent and shoulder, whereby said one notch accommodates saidoutward deflection of said rear slide portion.

6, A knife according to claim wherein said forward slide portioncomprises a tongue extending forwardly from said rear slide portion andhaving a width greater than the width of said slot, said tongue isremovable from said handle through the rear open end of said guidewaywhen said rear slide portion is deflected outwardly of said handle toclear said limit stop.

7. A knife according to claim 1; including a knife blade attached tosaid blade connecting means and extending forwardly of said slidethrough said guideway for extension and retraction of said bladerelative to said handle by longitudinal movement of said slide relativeto said handle.

8. A knife according to claim 7; wherein said handle includes flangesbounding said slot along opposite longitudinal sides thereof andextending over said guideway, said handle includes means within saidguideway slidably supporting said blade for movement through saidguideway in a plane generally parallel to and spaced from said flanges,said forward slide portion comprises a tongue extending between saidblade and flanges, said blade connecting means comprise releasablyinterengaging means on said blade and tongue and said tongue slidablyengages said flanges to retain said interengaging means in operativeengagement, said slide and blade being removable from said handle topermit replacement of said blade.

9. In a knife: a handle having a central guideway opening longitudinallythrough the forward end of said handle and laterally through alongitudinal slot in one side of said handle, a blade-actuating slidewithin and movable lengthwise of said guideway, said slide having frontand rear portions, said rear slide portion including a longitudinallyextending laterally resilient beam projecting through said slot forengagement by a finger of the users hand, means slidably supporting saidbeam on said handle at two longitudinally spaced supporting locations,whereby said beam is adapted to be deflected inwardly toward said handleby finger pressure on said beam intermediate said supporting locations,and coacting releasable locking means on said beam and handle fornormally locking said slide against movement relative to said handle andadapted to be released by inward deflection of said beam toward saidhandle to permit movement of said slide relative to said handle, saidfront slide portion including blade connecting means for attaching tosaid slide a knife blade to be extended and retracted relative to saidhandle by longitudinal movement of said slide relative to said handle,including a knife blade attached to said blade connecting means andextending forwardly of said slide through said guideway for extensionand retraction of said blade relative to said handle by longitudinalmovement of said slide relative to said handle, wherein said handleincludes flanges bounding said slot along opposite longitudinal sidesthereof and extending over said guideway, said handle includes meanswithin said guideway slidably supporting said blade for movement throughsaid guideway in a plane generally parallel to and spaced from saidflanges, said forward slide portion comprises a tongue extending betweensaid blade and flanges, said blade connecting means comprise releasablyinterengaging means on said blade and tongue and said tongue slidablyengages said flanges to retain said interengaging means in operativeengagement, said slide and blade being removable from said handle topermit replacement of said blade, wherein said guideway opens throughthe rear end of said handle, said blade supporting means compriselongitudinal grooves in opposing walls of said guideway slidablyreceiving the longitudinal edges of said blade and opening through therear end of said guideway, said handle includes a limit stop spacedlongitudinally rearwardly from said locking means on said handle andengageable with said rear slide portion for preventing movement of saidrear slide portion through the rear end of said guideway, said rearslide portion having a width no greater than the width of said slot andbeing deflectable laterally outward from said handle to clear said limitstop and thereby permit rearward movement of said tongue and blade fromsaid handle through the rear end of said guideway.

10. A knife according to claim 9; wherein said coacting locking meanscomprises a locking notch in one of said flanges and a detent projectinglaterally from the center of said beam for engagement in said notch tolock said slide and blade against movement relative to said handle whensaid beam is in its normal unstressed condition, said detent isretractable from said notch into said guideway to release said slide andblade for movement relative to said handle by inward deflection of saidbeam relative to said handle, said rear slide portion being deflectableoutwardly from said handle to clear said limit stop when said detent isaligned with said notch.

11. A knife according to claim 10; wherein said one flange has a secondlocking notch for receiving said detent, said notches are spacedlongitudinally of said handle, whereby said slide and blade may beselectively locked in two different positions relative to said handle,said detent includes a shoulder engageable under said one flange whensaid detent engages in said second notch for preventing outwarddeflection of said rear slide portion relative to said handle, saidfirst-mentioned locking notch has a width slightly greater than theoverall width of said detent and shoulder for accommodating said outwarddeflection of said rear slide portion relative to said handle to clearsaid limit stop and thereby permit separation of said slide and bladefrom said handle.

12. A knife according to claim 11; wherein said beam supporting meanscomprise front and rear beam supports joined to the front and rear endsof said beam, said front beam support is secured to the rear end of saidtongue, and said rear beam support rests slidably on the bottom wall ofsaid guideway.

13. A knife according to claim 1; wherein said beam supporting meansincludes front and rear beam supports secured to longitudinally spacedportions of said beam, whereby said beam is deflectable inwardly betweensaid supports.

References Cited UNITED STATES PATENTS 3,314,148 4/1967 Foellmi 301623,171,201 3/1965 Carifi 30-162 X 2,284,168 5/1942 Rickenbacker 30-162 X3,192,624 7/1965 Gringer 30-162 FOREIGN PATENTS 453,839 12/ 1949 Italy.

ANDREW R. JUHASZ, Primary Examiner.

G. WEIDENFELD, Assistant Examiner.

U .5. c1. X.R. 30-329, 337

